Therefore, for solving Outlook keeps prompting for password 2016, 2013, 2010, 2007 issues in quite effective and simple manner, a comprehensive list of solutions are mentioned and described here. The Simple Solution to Fix Outlook Keeps Asking For Password And Won’t Connect. The methods and fixes described here are simple and easy to follow. After you enter your new password (same to the password of your Mac account), Keychain Access creates an empty login keychain with no password. Click OK to confirm. (If you don't see a Reset My Default keychain button, close the preferences window and select the “login” keychain from the left side of the Keychain Access window.
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Symptoms
In Microsoft Outlook 2016 for Mac, you are repeatedly prompted for authentication while you're connected to your Office 365 account.
Cause
This issue occurs because of the presence of duplicate tokens in the keychain.
Resolution
Os X Outlook Keeps Asking For Password Office 365
Os X Outlook Keeps Asking For Password Settings
To resolve this issue in Outlook 2016 for Mac, install the February 2017 Outlook update (version 15.31.0) from the following Office website:
Workaround
To work around this issue, delete any cached passwords for your account, and also delete any modern authentication tokens from the keychain. To do this, follow these steps.
Note
These steps affect all Office applications that use modern authentication.
Quit Outlook and all other Office applications.
Start Keychain Access by using one of the following methods:
- Select the Finder application, click Utilities on the Go menu, and then double-click Keychain Access.
- In Spotlight Search, type Keychain Access, and then double-click Keychain Access in the search results.
In the search field in Keychain Access, enter Exchange.
In the search results, select each item to view the Account that's listed at the top, and then press Delete. Repeat this step to delete all items for your Exchange account.
In the search field, enter adal.
Select all items whose type is MicrosoftOffice15_2_Data:ADAL:<GUID>, and then press Delete.
In the search field, enter office.
Select the items that are named Microsoft Office Identities Cache 2 and Microsoft Office Identities Settings 2, and then press Delete.
Quit Keychain Access.
Note
When you start Outlook, you are prompted to authenticate.